I heard that we are grateful to the Ebishter's motherly side. We are thanking Gd for Mercy and so we appeal to the grammatically Feminine words for Gd (such as the Shechinah);
as the above comment states. Remember Shabbat is the Queen. And since we were created in Tzelem Elo-kim as demi gods with creative powers, this must mean that everyone has both male and female components to our soul.

If we are speaking to His motherly side (whatever that means) then why do we use the word אתה in the next word?
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Double AA♦Feb 3 '13 at 16:11

Because the Ebishter is also the Shechinah that rests above someone's bed during moments of need. The same Shechinah that is the Shabbat Queen. That is what Motherly side means. That when we require a special blessing be made for healing, lo aleinu... we call upon the Mother not the Father. Part of our problem as Jews is many of us do not truly accept new data with anything other than show me the source! You are allowed to think, we do not have to be formed by the minds of others. WE ARE created in the Tzelem Elokim. And by the way how come Judaism is misogynistic? And don't give me pedestal!
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Richard AckermannFeb 6 '13 at 15:09

Was ^^^ a response to my question? If so I don't understand how it answered it.
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Double AA♦Feb 6 '13 at 18:02

As avi answered, (1) Lach is an acceptable form for males in Biblical Hebrew. I think that one will typically find this in more polite speech.

More than that,

(3). It is an alternation in Biblical Hebrew for the pausal form. Just as Lemech becomes Lamech at an etnachta or silluq (or sof pasuk), so does Lecha become Lach in these positions. Prayer is based, often, on Biblical Hebrew, and indeed employs pausal forms. E.g. gashem, atta with a kamatz and stressed on the first syllable, and so on.

In terms of (2), that it is a way of referring to Hashem in the feminine, I doubt it because Modim continues she-atta rather than she-at.

+1, but this answer is incomplete without JXG's, which explains why the pausal form is used here.
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msh210♦Oct 26 '11 at 16:57

JXG doesn't explain what the pausal form is, though. This does. And Josh says that prayer is often based on Biblical Hebrew (though he could have indicated the source for this as JXG does). I +1 both.
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Seth JOct 26 '11 at 20:58